The market for knife sharpening

There was a time when knife sharpeners brought their grindstones to the meat packers and butchers who were their main customers, and sharpened customers' knives on customers' premises. Now, the NY Times reports, the model is to rent a double set of knives to customers (who now include restaurants), so that the knife sharpener can come in and exchange all the dull knives for sharp ones, and sharpen the knives on his own premises: Venerable Craft, Modern Practitioner.

Apparently this business is one with ethnic, networked roots:
"Mr. Ambrosi’s grandfather, who came to the United States in the 1920s, hailed from the poor village of Carisolo. The village, with two neighboring towns of Pinzolo and Giustino, produced many of the more than 100 commercial knife sharpeners at work today in North America, sharpeners said. "
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"At first the immigrants came mainly to New York, but soon their offspring scattered to stake out new routes, a dozen sharpeners across the country said in interviews. Ambrosis with grindstones do business in Connecticut, New Jersey and Ohio, as well as boroughs of New York. The Binellis set up knife-sharpening businesses in Detroit, Chicago and Medford, Mass.; the Maganzinis ended up in and around Boston. The Povinellis set up shop in Buffalo and ventured to North and South Carolina and Arizona; offshoots of the Nella family went to Toronto and Vancouver, as well as Long Island, Seattle and West Jordan, Utah.

"Robert Ambrosi’s grandfather traveled the Bronx in a horse-drawn cart with a grindstone powered by a foot pedal, serving, like the other knife sharpeners, mainly butchers and meatpackers.

"Mr. Ambrosi’s father used a grindstone fueled by a battery carried in a truck. The battery had to be plugged in each night in the garage to recharge. Then in the 1950s came the great innovation — double sets of knives — that eventually freed the Ambrosis to set up their first shop."
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"Some of the northern Italian knife sharpeners still function in the old style, as members of the New York Grinders Association. The rules used to be simple: Don’t mess with someone’s turf. Stick to your own route — the one you inherited from your father or grandfather. Avoid the vendettas that have overtaken sharpeners in other cities.

“People will trade stops,” said Rinaldo Beltrami, the association’s president.

"Mr. Ambrosi, who let his membership in the association lapse, said, “I was brought up in that way of thinking.” Yet he will still sometimes appease a competitor by saying, “Let’s sit down, we’ll have a meeting, we’ll make a borderline — I won’t bother you.”

"Yet his sons have been knocking on doors to establish new routes, and Mr. Ambrosi has developed a Web site and a mail-order service, because his sons need enough business to sustain their future families, too. "